I worked up some stats for my 6mm AI, 87 VMax, 50.5 gr, VN165.
10 twist
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6mm Rem, PPU brass, COW FF, annealed, necks turned to .268.
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At a 95% probability I could expect mean velocites to range from a hi of 3482 down to a low of 3456. My sample size was 10. Accuracy about .5 MOA. This spread sheet will work with other data like powder weight & ogive/land location.
When I shot the 87 VMax out of a 8 twist, 6mm-06 at slightly less velocity the bullets blew up, like gray smoke 20 feet or so out.
This load needs more work to reduce extreme spread, giving up 100 fps or less would be worth it to get spreads less than 20.
Possibly, better brass like 7mmX57 Norma would reduce extreme spreads. Weighing powder is a pain but might reduce extreme spread, these loads were directly thrown from measure, VN165 is about like H4831 SC in grain size. I also have some RL23 that I might try.
The 6mm 95 Berger VLD with a 8 twist is a good combo. The 95 Berger VLD has a really good form factor & can be driven at high velocities but needs a faster twist than 10.
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Group on left was shot with my old 8 twist 6mm AI barrel with 95 Berger VLD & H4831 at 300. Other .204 Ruger 300 yard groups were included. Messy targets, back then, stuff like this would not go.